Computer systems such as personal computers commonly include an expansion bus arrangement. PCI, ISA, and EISA are examples of expansion bus standards commonly used in personal computer systems. These expansion bus arrangements allow additional electrical components and circuitry to be added to the computer system to increase or enhance system capabilities. The additional circuitry is mounted on a printed circuit board commonly referred to as an option card (also known as an expansion card or add-on card). Option cards include a connector strip along one side of the printed circuit board. This connector strip is adapted to be received in a connector slot associated with the expansion bus. An expansion bus arrangement associated with a computer system commonly includes several option card connectors, each having a connector slot for receiving the connector strip edge of an option card.
When an option card is properly received in a slot-type option card connector, electrical pads mounted on the connector strip of the card make electrical contact with receiving elements mounted within the connector slot. The frictional engagement between the connector strip and receiving elements in the connector slot also holds the card in place. In most cases, the option card includes an additional mechanical connector at one end. This additional mechanical connector connects the option card to a frame in which the slot connector is mounted. The additional mechanical connection may be made with a screw or other fastening device, and is intended to help hold the option card in a properly connected position in the respective connector slot.
The connection between the option card connector strip and the connector slot is critical to the proper operation of the system. In the event that the connector strip becomes fully or partially dislodged from the connector slot, the option card and computer system cannot operate properly. An option card connector strip may become dislodged from its connector slot in any number of ways. In some cases, the connector strip comes loose from its connector slot as the computer system is transported or handled. Also, where the frame is misaligned with the system motherboard, mechanically connecting the option card to the frame may pull one end of the connector strip from the connector slot. Regardless of the manner in which an option card becomes dislodged, the resultant error in the computer system commonly results in a service call from the customer and may lead to customer dissatisfaction with the computer system.
Numerous devices have been developed for holding a computer system option card in place in its respective connector. A consistent shortcoming of these prior devices is that the devices required some modification to the computer system or some special structure associated with the computer system. Also, these prior option card retainer devices were cumbersome to install given the limited space available between option card connectors in the computer system.